1. Field of the Invention
This invention relates generally to computer networks, and, more specifically, to Internet Protocol (“IP”) based computer networks.
2. Discussion of the Related Art
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present invention, which are described and claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
The IP multimedia subsystem (“IMS”) is a standardized architecture for providing a variety of multimedia services, such as video, audio, instant messaging, online games, and/or telephone calls over IP networks, such as the Internet. The IMS standard employs a variety of different communication protocols to establish and manage these multimedia services. One of these standards, known as session initiation protocol (“SIP”), provides a standard for creating, managing, and terminating communication sessions between users (referred to as “user agents,”) within the IMS network. User agents in the IMS network may include wireless telephones, voice over IP telephones, computers, personal digital assistants (“PDAs”), or a variety of other suitable communication devices. One example of a SIP standard is the 3GPP SIP standard propagated by the 3rd Generation Partnership Project (“3GPP”).
The SIP standard employs a variety of transmissions, known as SIP messages that are passed between two user agents via one or more SIP servers, such as SIP proxy servers and SIP back to back user agents (“B2BUA”). SIP messages typically include information related to the establishment and teardown of a particular communication session. For example, a SIP message may describe which user agent is initiating the communication, what IP port to use for the communication, what decoding scheme to follow, and so forth. When one user agent wishes to communicate with another user agent, the initiating user agent transmits the SIP message to a proxy server within the IMS network. This proxy server will then transmit the SIP message through one or more other proxy servers in route to the destination user agent. The proxy servers are typically employed because the initiating user agent typically does not know the exact address of the receiving user agent and/or application servers that may provide connection or support for the communication session. As such, SIP messages are transmitted to proxy servers that forward the request to the proper place. After a predetermined number of SIP messages are exchanged (12, for example) a communication session between the two user agents may be established.
In a large IMS network with millions of potential user agents and proxy servers, several thousand or more SIP messages may be processed by individual proxy servers at any given time. Conventional IMS networks are configured to process these requests in a first in-first out (“FIFO”) methodology. In other words, the proxy servers are configured to process SIP messages in the order in which they are received. For example, when a proxy server receives its first SIP message, it begins to process that message. If another SIP message is received while the proxy server is processing the first message, it is placed in a SIP message queue behind the first message. If yet another SIP message is received while the proxy server is processing the first message, this third message is placed in the queue behind the second message and so forth. When the proxy server finishes processing the first message, it will start processing the second message regardless of how many messages are in the queue and regardless of the attributes of the messages in the queue.
One or more of the embodiments described herein may be directed towards one or more of the aspects described above.